Portland Community College | Portland, Oregon

For CH 151 Competency Exam information, visit the following website:

http://www.pcc.edu/resources/testing/proctored/chemistry.html

Chemistry 221Z is the first of a three term chemistry sequence designed to provide a year of general chemistry to science majors (4 credits/term). When taken with 227Z, it will meet transfer school requirements for such science majors as: chemistry, physics, chemical engineering, pre-medicine, and other pre-professional programs. The lecture time is used to provide the student with foundational chemical concepts and mathematical applications to chemistry. The 227Z co-requisite laboratory re-enforces concepts presented in lecture and provides the student a hands-on opportunity to explore these.

Upon successful completion of the course, students should be able to:

1. Describe the phases and classifications of matter and differentiate between physical and chemical properties.
2. Represent physical measurements using SI and derived units and demonstrate systematic problem-solving including unit conversion.
3. Use the periodic table to solve problems in chemistry.
4. Describe the principles of electromagnetic energy, the Bohr model and quantum theory, and use electron configurations to identify periodic variations in chemical properties.
5. Interpret and apply ionic and covalent bonding theories including Lewis structures, formal charges, resonance, molecular structure, and polarity.
6. Quantify the composition of substances and solutions.
7. Identify and name a variety of elements, ions, ionic compounds, and covalent compounds.
8. Write, balance, and classify chemical reactions and solve foundational stoichiometry calculation.

Core Outcome: Cultural Awareness

Demonstrate appropriate cultural awareness within the general chemistry field.

Core Outcome 6:  Self Reflection

Demonstrate effective self-reflective skills within the general chemistry field.

Students will be able to..

1. Describe the phases and classifications of matter, and differentiate between physical and chemical properties.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

2. Represent physical measurements using SI and derived units and demonstrate systematic problem solving including unit conversion.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

3. Use the periodic table to solve problems in chemistry.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

4. Describe the principles of electromagnetic energy, the Bohr model and quantum theory, and use electron configurations to identify periodic variations in chemical properties.

Dual Nature of Light and Matter

4a. Compare the regions of the electromagnetic spectrum (UV, visible, IR, x-ray) in terms of energy, frequency, and wavelength. 

4b. Interconvert frequency, wavelength, and energy of light. 

4c. Explain or apply the photoelectric effect - how the threshold frequency supports the particle model of light.  

4d. Discuss and give examples of wave-particle duality.  

Electronic Structure of the Atom

4e. Draw a Bohr model representing an atom. 

4f. Given a Bohr model of an atom, identify emission and absorption processes.

4g. Calculate the frequency, energy or wavelength of an electron transition in a hydrogen atom.  

4h. Rank electron transitions in terms of energy, frequency and wavelength. 

4i. Explain the major limitation of the Bohr model.  

4j. Given a set of quantum numbers, describe what each number identifies.  

4k. Name and describe the hierarchy of quantum numbers: energy levels, sublevels, orbitals, and spin.  

4l. Given a two- or three-dimensional representation of a subshell, assign appropriate n- and l- numbers or subshell designation. 

4m. Given an electron in an orbital box diagram, assign quantum numbers to a subshell, orbital, or electron. 

4n. Apply the Pauli Exclusion Principle and Hund’s Rule.  

Periodic Trends

4o.Given a many-electron atom, identify and describe shielding by inner electrons.  

4p.Given a many-electron atom, explain the difference between effective nuclear charge (core charge) and total nuclear charge. 

4q.Given a periodic table, differentiate between the s-, p-, d-, and f-blocks. 

4r.Given a periodic table, state the order of subshells in terms of increasing energy.  

4s.Given an element or monatomic ion, write the electron configuration in standard and noble gas notation.  

4t.Define and explain the periodic trends in atomic size, ionization energy, and ionic size in terms of electrostatics, shielding, and effective nuclear charge (core charge).  

4u.Given a series of ionization energies for an element, identify valence and core electrons.  

4v.Given an element, electron configuration, or orbital box diagram, interpret the electronic structure and describe the element as either diamagnetic or paramagnetic.  

5. Interpret and apply ionic and covalent bonding theories, including Lewis structures, formal charges, resonance, molecular structure, and polarity.

Chemical Bonding

5a.State why chemical bonds form.  

5b.Identify the three types of bonding that occur between metal and nonmetals - metal with nonmetal, nonmetal with nonmetal, and metal with metal.  

5c.Given two ionic compounds, predict the stronger ionic bond based on the charges and the size of the ions.  

5d.Demonstrate or explain physical properties of ionic solids (mechanical properties, thermal and electrical conductivity).  

5e.Sketch or describe the attractive and repulsive forces that create a covalent bond.  

5f.Given a potential energy curve for the formation of a covalent bond, discuss the absolute and relative changes in attractive and repulsive forces as a function of internuclear distance.  

5g.Given a potential energy curve, identify the bond length and energy.  

5h.Predict the bond order, energy and length of a series of covalent bonds. 

5i.Predict bond strength in a series of covalent bonds based on the periodic trend of atomic size.  

5j.Classify a covalent bond as a single, double, or triple bond and identify the number of electrons present. 

5k.Given a periodic table of electronegativities of elements, differentiate between nonpolar covalent, polar covalent and ionic bonds. 

5l.Designate a polar covalent bond with the proper charge notation (δ+ and δ-).  

Lewis Structures

5m.Given a periodic table and chemical formulas, draw Lewis structures to represent molecules and polyatomic ions in two dimensions.  

5n.Define the terms resonance structure and resonance hybrid and explain how they differ.  

5o.Evaluate Lewis structures with the octet rule, formal charge and electronegativity to select the resonance structure that contributes the most to the resonance hybrid. 

5p.Identify and draw molecules that are exceptions to the octet rule (electron-deficient, expanded octets, odd number of electrons).  

Valence Shell Electron Pair Repulsion (VSEPR) Theory

5q.Know the electron group arrangements and the resulting molecular geometries predicted by VSEPR for central atoms with 2-6 electron regions. 

5r.Identify and name the two non-equivalent positions, the equatorial and axial positions, in the trigonal bipyramidal structure and predict the placement of nonbonding electrons. 

5s.Given a formula and periodic table, draw a Lewis structure and identify, name, and draw both the electron domain geometry (aka. electron group arrangement) and molecular shape for any structure. 

5t.Given a molecule, predict the shape and the resulting bond angles. 

5u.Predict the effect of nonbonding electron pairs on the resulting bond angles.  

5v.Evaluate the shape of the molecule and the contributions of the polar bonds or nonbonding electron pairs to determine if a molecule is polar, thus having a dipole moment. 

5w.Given a Lewis structure, draw a three-dimensional structure employing the correct wedge dash notation. 

Covalent Bonding Theories (Valence Bond Theory and Molecular Orbital Theory)

5x.Given simple diatomic molecules, explain bonding as the overlap of atomic orbitals.  

5y.Given a molecule such as methane, discuss the differences between the observed molecular geometry and the molecular geometry based on the overlap of atomic orbitals. 

5z.Identify the atomic orbitals that are mixed to form the hybrid orbitals consistent with a given molecular shape.  

5aa.Describe the spatial overlap (end-to-end or side-to-side) of atomic orbitals that result in the formation of a sigma or pi bond.  

5bb.Predict the hybridization of the central atom in a molecule.  

5cc.For simple diatomic molecules, explain and illustrate the bonding and antibonding molecular orbitals.  

5dd.Identify the bonding and antibonding molecular orbitals that result from overlap of two s or p atomic orbitals.  

5ee. Predict stability and bond order of a molecule from its molecular orbital energy diagram.  

6. Quantify the composition of substances and solutions.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

6a.Given two of the following (the mass of solute, volume of solution, and molarity), calculate the third.

7. Identify and name a variety of elements, ions, ionic compounds and covalent compounds.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

8. Write, balance and classify chemical reactions and solve foundational stoichiometry calculations.

Please refer to the required prerequisite course CH 151 objectives for more detailed information and review the relevant topics accordingly.

8a. Given a balanced chemical equation and masses of multiple reactants, determine the limiting reagent, calculate the maximum mass of products that can be formed, and calculate the mass of excess reactant that remains. 

8b. Given a balanced chemical equation, the mass of one reactant, the stipulation that the other reactants are present in excess, and an actual yield, calculate the theoretical yield and percent yield.